Difference between revisions of "Kernel Building"

From Openembedded.org
Jump to: navigation, search
m
(Kernel configuration)
Line 22: Line 22:
 
== Kernel configuration ==
 
== Kernel configuration ==
  
The default .config file used is placed in ???/defconfig.
+
=== Default configuration ===
  
 +
The default .config file used is normally placed somewhere under recipes/linux named '''defconfig'''.
 +
You may want to search for it, say for vmware:
  
If you need to customize the kernel configuration, run the menuconfig task by:
+
  find recipes/linux -name "vmware*"
 +
 
 +
And you find it in:
 +
  recipes/linux/linux/vmware/defconfig
 +
 +
 
 +
=== Apply custom patches ===
 +
FIXME
 +
 
 +
=== Customize configuration ===
 +
If you need to customize the kernel configuration, you may run the menuconfig task by:
 
   bitbake -c menuconfig virtual/kernel
 
   bitbake -c menuconfig virtual/kernel
  
'''Note:''' by default this command requires you to run in X Windows.
 
  
 +
'''Note:''' by default these command requires you to run in X Windows. If you want to work in text terminal only, here's a [[How_to_use_bitbake_without_X_Windows|how to]].
 +
 +
=== Compile ===
 
After that, you can compile the kernel by:
 
After that, you can compile the kernel by:
 
   bitbake -f -c compile virtual/kernel
 
   bitbake -f -c compile virtual/kernel
  
 +
=== Fine control ===
 +
If you need more control over the configuration and compile process, you can go to the shell by:
 +
  bitbake -c devshell virtual/kernel
 +
The build environment will be well setup for you; you can run regular make commands like <tt>make bzImage</tt> ...etc
 +
 +
=== Preserving the custom configuration ===
 +
Changes are lost if you remove the tmpdir or do a "<tt>bitbake -c clean virtual/kernel</tt>", so you
 +
may consider replacing the defconfig with it.
  
 
[[Category:User]]
 
[[Category:User]]
 
[[Category:FAQ]]
 
[[Category:FAQ]]

Revision as of 08:11, 21 October 2010

Default Build

For a default build, just run:

 bitbake virtual/kernel

After done, you can collect the built image from under the deploy folder, for example: build/tmp/deploy/glibc/images/vmware/bzImage-vmware.bin.


Kernel image type

What kind of kernel image to build is controlled by the variable KERNEL_IMAGETYPE. For example, build image for u-boot

 KERNEL_IMAGETYPE = "uImage"

Select kernel version

To select which kernel version to build, edit config file ??? and set variable ??? to , for example, 2.6.35.

Kernel patches

Where to place the patch files and how to configure OE to apply them?

Kernel configuration

Default configuration

The default .config file used is normally placed somewhere under recipes/linux named defconfig. You may want to search for it, say for vmware:

 find recipes/linux -name "vmware*"
 

And you find it in:

 recipes/linux/linux/vmware/defconfig

Apply custom patches

FIXME

Customize configuration

If you need to customize the kernel configuration, you may run the menuconfig task by:

 bitbake -c menuconfig virtual/kernel


Note: by default these command requires you to run in X Windows. If you want to work in text terminal only, here's a how to.

Compile

After that, you can compile the kernel by:

 bitbake -f -c compile virtual/kernel

Fine control

If you need more control over the configuration and compile process, you can go to the shell by:

 bitbake -c devshell virtual/kernel

The build environment will be well setup for you; you can run regular make commands like make bzImage ...etc

Preserving the custom configuration

Changes are lost if you remove the tmpdir or do a "bitbake -c clean virtual/kernel", so you may consider replacing the defconfig with it.